Typically used printed circuit boards (PCBs) have a substrate on which a copper thin film circuit is formed and which is coated, and then has various components inserted therein and is operated through transmission of electrical signals. Such typical printed circuit boards, however, have the limitation of the substrate having a lower capacity for transmitting electrical signals than the processing ability of the components, or electrical devices. In particular, such electrical signals are sensitive to the external environment, and noise is generated, thus presenting considerable obstacles for electronic products requiring high precision. To alleviate such limitations, instead of a metallic circuit such as copper, an optical printed circuit board using an optical waveguide has been developed with greater reduction of electrical wave interference and noise, to allow production of high precision, advanced equipment.
FIG. 1 is a conceptual view showing the structure of an optical printed circuit board according to the related art.
Referring to FIG. 1, an optical printed circuit board according to the related art, for achieving an optical connection, includes a light emitting device 5, a transmission processing chip 7, a light collecting device 6, a reception processing chip 8, an optical connecting block 1, and an optical waveguide 10.
Specifically, a printed circuit board 3 is provided to mount the light emitting device 5, transmission processing chip 7, light collecting device 6, and reception processing chip 8, and a guide pin 2 provides connections between the optical connecting block 1 and the optical printed circuit board 4, between the optical connecting block 1 and the light emitting device 5 and the light collecting device 6.
However, in this related art optical printed circuit board, noise can be generated in the line connecting electrical signals between the printed circuit board 3 and the optical printed circuit board 4, and optical loss can occur from misalignment at a portion connecting the light emitting device 5 and light collecting device with the optical connecting block 1, or at a portion connecting the optical connecting block 1 with the optical waveguide 2 inside the optical printed circuit board 4.
Also, when the guide pin 2 is used, the guide pin 2 may be dislodged or deformed from vibrations or temperature variation during use.